Tag: science & technology

The energy of a single photon is given by E = hv, where h is Planck's constant and v is the frequency of the electromagnetic radiation. This is a fundamental equation in quantum physics, first proposed by Einstein to explain the photoelectric effect.

The photoelectric effect is used for amplification in devices like photomultiplier tubes, where a single photon can trigger a cascade of electrons, greatly amplifying the signal. It is not used for lighting (it converts light to electricity), cooling, or general-purpose applications.

In beta decay, a neutrino (or antineutrino) is always emitted along with the beta particle. In beta-minus decay, an antineutrino is emitted; in beta-plus decay, a neutrino is emitted. This conserves lepton number and accounts for the continuous energy spectrum of beta particles.

Neutrinos are electrically neutral particles, as their name suggests ('little neutral one'). They have no electric charge, which allows them to pass through matter almost unaffected. They are not positive, negative, or variably charged.

Neutrinos have non-zero but extremely small mass. While once thought to be massless, neutrino oscillation experiments proved they have mass. Each neutrino flavor has a different tiny mass, much smaller than an electron's mass.

Beta particles are high-energy electrons or positrons emitted during beta decay. In beta-minus decay, an electron is emitted; in beta-plus decay, a positron is emitted. They are not photons or excited versions of particles.

The antiparticle of the neutrino is the antineutrino. Just as particles have corresponding antiparticles, the neutrino has its antiparticle counterpart with opposite lepton number. Antineutrinos are emitted in beta-minus decay.

The positron is the antiparticle of the electron. It has the same mass as an electron but opposite (positive) charge. Positrons are emitted in beta-plus decay and were one of the first antiparticles discovered.

An alpha particle is a helium nucleus, consisting of 2 protons and 2 neutrons. It's essentially a helium atom that has lost both electrons (not just one). Alpha particles are emitted in alpha decay and have a +2 charge.